$(document).ready(function () {
    var uploader = new qq.FileUploader({
        element: $('#uploader')[0],
        action: '/File/Upload',
        onComplete: upload_back
    });
});

function upload_back(id, fileName, responseJSON) {
    var ids = '';
    for (var i in responseJSON.List) {
        ids = ids + responseJSON.List[i].Id;
        ids = ids + '|';
    }
    ids = ids.substring(0, ids.length - 1);
    $("form").append('<input type="hidden" name="filesUploaded" value="' + ids + '" />');
}